jl audio sub rattle?

I just installed a jl 8w0 subwoofer in the factory sub location on a 2002 tahoe. I lexteled (like silicone)the all the area around the sub and made sure that the box is air tight and no air is coming out. The problem is that on certain notes when the speaker is playing it rattles veery noticeably. I have checked a hundred times and am positive that the sound is from the speaker and not any loose objects. It almost sounds like the dustcap is rattling. Does anybody have any ideas as to what is causing this...or even better how to fix it?

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Dyer

Isolate that frequency that causes the rattling so you can replay it while you check:  the sheet metal in the vicinity of the sub.  Press on the car metal while that freq hits and see if the rattling disappears,  and if so use sound damping.  I think a fault in the speaker itself would show up on more than one frequency.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

it could just be that an aftermarket sub hooked up to a factory amp(if you have this system) sounds like crap due to the amp and sub being matched to eachother and thats basically the best sound you will get without installing a new amp.

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94 Pontiac Sunbird 3.1 V6
alpine deck
audiobahn 3.5 fronts w/ tweeters
audiobahn 6.5 rears w/ tweeters
* sold rest of system to save up towards new car. $3000 spent on it.

I don't have the sub running off the factory amp...that would be crap. I have an aftermarket amp. Maybe I need to be more clear, the sub doesn't rattle on just one note, but more noticeable on some than others. It rattles throughout the songs.

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Dyer

alrite. it could be the frequency range you have set is off to the subwoofers specs. also you could have the polarity mixed on the subwoofer itself that will cause a phase shift. you can find out if it is correct by using a size c or d battery and matching the + and - to the speaker terminal. if it moves out, wired correctly, moves in, wired reversed. you probably already know this stuff so sorry if im repeating. it also could be a problem with the subwoofer itself. i had a mtx subwoofer a couple years ago that had the voice coil disconnect from the subwoofer frame and rattle.

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94 Pontiac Sunbird 3.1 V6
alpine deck
audiobahn 3.5 fronts w/ tweeters
audiobahn 6.5 rears w/ tweeters
* sold rest of system to save up towards new car. $3000 spent on it.

also try dynamat behind the subwoofer because it may be the body panels on your suv too.

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94 Pontiac Sunbird 3.1 V6
alpine deck
audiobahn 3.5 fronts w/ tweeters
audiobahn 6.5 rears w/ tweeters
* sold rest of system to save up towards new car. $3000 spent on it.

ok, first off remove the speaker from the enclosure and get some extra wiring and then play the subwoofer out of the enclosure (at low volume so u dont screw it up). Listen for any rattling and watch the sub to see if maybe the tensel it hitting the cone or if the dustcap has become lose somewhere. If it is the dustcap I'd suggest superglue as a quick solution but you'd be better of with a silicon based adehsive to make it a more durable finish. If the tensel wires are hitting the cone then your gona need to find a way to shorten the tensels, maybe solder a little of it down. I'm thinking its probably not the tensel, because it should be the proper lenght out of the JL factory. My only other thoughts on this would be that something has managed to work its way into the dustcap or event into the magnetic gap and is being thrown around by the air movement when the sub is playing. Bascially ur gona need to take this sub out and examine it to figure out exactly what is causing this rattle.

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"Shiny chrome when used in conjunction with bikini models is particularly effective in inducing brain deficit disorder"

02 Jeep Grand Cherokee

Monster System on its way.

I appreciate your help...don't worry about repeating yourself. Just b/c I may know it, someone else reading the post may not. This forum is for information, your giving it! I figured I would have to pull the sub and analyze it closely...just hoping someone knew of some magic.

Such is life...<sigh>


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Dyer